The present invention relates to an electric fan apparatus, and more particularly, to an improved electric fan apparatus suitable for employing in a plurality of fan impellers, e.g. three impellers, thus sending the wind generated by the fan impellers to 360 degrees in all directions.
Electric fans have been used for many years for wind cooling in residential, commercial and industrial buildings. At the same time, the typical desk-fan construction wherein one fan impeller forming a plurality of blades is only mounted coaxially with a drive motor permits its air flow to a narrow range even though the fan head may be angularly moved to the right and the left sides.
For that reason, when the fan impeller is angularly moved to direct to the right side, the left side can not be covered with the wind, thus remaining under hot state.
As the same manner, when the fan impeller is angularly moved to direct to the left side, the right side will be under hot state.
Accordingly, the aforementioned desk-fan presents a problem not being able to match with the users' satisfaction because of sending the wind to the narrow range.
In another conventional electric fan, a wind direction shifting plate has been used as means for shifting the direction of a wind generated by a fan impeller rotated by a motor, without shifting the air sending direction by the fan impeller.
In such arrangement, the wind direction shifting plate serves as a guide plate which the wind direction can be changed from one position to other position, however, the width of the wind flow can not be expanded but the wind direction can be only changed, and accordingly the aforesaid electric fan creates a problem the same as the above-described desk-fan.
Thus, none of the aforementioned electric fan apparatus discloses the desired features of the wide wind range in all directions, e.g. 360 degrees, and simple operation and adjustment of the fan itself for widening air flow width, especially in combination with fan apparatus of such manifold construction as to generate warm air flow in case of necessity.